Name __________________________________ Period _____ Chemical Formulas, Reactions and Equations Test Review This review will prepare you for your assessment over the following readiness TEKS: •
8.5C (R) Interpret the arrangement of the Periodic Table, including groups and periods, to explain how properties are used to classify elements •
8.5D (R) Recognize that chemical formulas are used to identify substances and determine the number of atoms of each element in chemical formulas containing subscripts •
8.5E (R) Investigate how chemical reactions indicate that new substances with different properties are formed …and the following supporting TEKS: •
8.5F (S) Recognize whether a chemical equation containing coefficients is balanced or not and how that relates to the law of conservation of mass Please use your notes in your science notebook as well as pages 124-­‐161 in your Texas Science Fusion textbook to complete this review packet. 1. The Periodic Table. Complete the following passage. All the different elements are arranged in the ___________________________ table. Elements with similar properties are found in columns called _________________ . The rows are known as _____________________ . The non-­‐metals are found on the _______________ side of the periodic table and the metals are found on the _______________ side of the periodic table. 2. Special Groups. Label the following terms on the periodic table: • Alkali Metals • Metalloids • Alkali Earth Metals • Noble Gases • Groups • Non-­‐metals • Halogens • Periods • Metals • Transition Metals Using the same word bank above, match the correct group to the descriptions below: 1. This group can have 1-­‐2 valence electrons, which they lose when forming bonds. They can also use the 2 outermost orbitals when bonding with other elements. _________________________ 2. This group contains the most reactive metals and holds only one valence electron in their outermost shell. They react violently with water! _____________________________________ 3. This group has a full outer shell of valence electrons and rarely if ever reacts with other elements. _____________________________________________________________________ 4. This group has 7 valence electrons, which explains why they’re the most reactive non-­‐metals. They react with #2 above to form salts. ______________________________________________ 3. Valence electrons. Use a marker to color ONLY the valence electrons. How many valence electrons does each atom have? __________ Finish the sentence: Elements in the same group have the same number of __________________ electrons therefore they react similarly. 4. Chemical Reactions, Formulas and Equations. Define the following vocabulary (or make flash cards): Chemical Formula Chemical Equation Chemical Reaction Compound Subscript Product Atom Precipitate Element Coefficient Reactant Molecule Physical Property Chemical Property 2. Counting Atoms. Complete the table below: Chemical Formula 3H2SO4 KPO3 7CaCO 2FeCl2 Elements Present and # of Atoms for Each Total Number of Atoms Number of Molecules 3. Physical and Chemical Changes. Identify the following as a physical change (P) or chemical change (C ) . _______ Burning gasoline ______ Mixing 2 powders _______ B
reaking g
lass ______ Rust on a piece of Iron _______ Leaves changing color _______ Baking soda and vinegar bubble _______ C
hopping w
ood _______ Ice melts on a sunny day _______ Steam rises form boiling water _______ Mold grows on a piece of bread What is the difference between physical and chemical change? Include the words “physical and chemical change” in your response. _____________________________________________________________________________________________________________________
_____________________________________________________________________________________________________________________ 4. Indicators of a Chemical Reaction. What are the four clues that demonstrate a chemical reaction is taking place? 1. ________________________________ 3. __________________________________ 2. ________________________________ 4. __________________________________ 5. Heat Transfer. What is the difference between an endothermic and an exothermic reaction? Include the terms “endothermic” and “exothermic” in your response. _______________________________________________________________________________________
_______________________________________________________________________________________ 6. Balancing Equations. Determine which of the following equations are balanced. • Put a CIRCLE around the REACTANTS and a BOX around the PRODUCTS. LABEL the YIELD SIGN. • COUNT many atoms there are for each element. • TOTAL the number of atoms for each side. • Confirm if the equation is balanced or not. 1. 2Na + O2 → Na2O Sodium= _____ → Sodium= _____ Oxygen= ______ Oxygen= ______ Total= ________ Total= ________ Balanced? ________________________________________________ 2. 2 NaF +
Br2
à
2 NaBr
+
Sodium= _____ → Sodium= _____ Flourine= ______ Bromine= ______ Flourine= ______ Bromine= ______ F2 Total= ________ Total= ________ Balanced? ________________________________________________ 3. CH4 + 2 O2 → CO2 + 2 H2O Carbon= _____ → Carbon= _____ Hydrogen= ______ Hydrogen= ______ Oxygen= ______ Oxygen= ______ Total= ________ Total= ________ Balanced? ________________________________________________ 7. Law of Conservation of Matter/Mass. What does the law of conservation of matter/mass state? _______________________________________________________________________________________ _______________________________________________________________________________________